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yaser · #15 06-10-2013, 10:21 PM

Quote:

Originally Posted by nkatz

Is P(D|h=f) a function of D or h or both?

Let us first clarify the notions. The data set ${\cal D}$ has one data point in it which is either

(heart attack) or

(no heart attack). Being a function of ${\cal D}$ means being a function of that value ( $\pm 1$ ), so indeed $P({\cal D}|h=f)$ is a function of ${\cal D}$ , and it so happens in this problem that the value is fixed at

. The probability $P({\cal D}|h=f)$ is also a function of

(which happens to be the same as

according to what we are conditioning on).

Since ${\cal D}$ is fixed, this leaves $P({\cal D}|h=f)$ as a function of

only.